package thread;

import sun.awt.image.ImageWatched;

import java.util.*;

public class SyncDemo4 {
    public static void main(String[] args) {
        //List<Integer> c = new ArrayList<>();

        //List<Integer> c = Collections.synchronizedList(new ArrayList<>());
        //List<Integer> c = Collections.synchronizedList(new LinkedList<>());
        Set<Integer> c = Collections.synchronizedSet(new HashSet<>());
        Thread t1 = new Thread(){
          public void run(){
              for (int i=0;i<1000;i++){
                  c.add(i);
              }
          }
        };

        Thread t2 = new Thread(){
            @Override
            public void run() {
                for (int i=0;i<2000;i++){
                    c.add(i);
                }
            }
        };
        t1.start();
        t2.start();

        try {
            Thread.sleep(50);
        } catch (InterruptedException e) {
        }
        System.out.println(c.size());


    }
}
